Heat oil in a large saucepan over medium heat. Add the onion, carrot and garlic, cook until softened, about 5 minutes. Add the lentils, minced chipotle pepper and stock, stir to combine. Bring to a boil, reduce to a simmer, cover and cook for 20 minutes.
While the soup simmers, make the chipotle sauce by whisking together Astro Original yogourt with adobo and a pinch of salt. Season soup with salt and pepper. Divide between bowls and top with a dollop of chipotle sauce and a sprinkle of freshly snipped chives.